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How to: Embed a Manifest Inside a C/C++ Application

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It is recommended that a C/C++ application (or library) have its manifest embedded inside the final binary because this guarantees correct runtime behavior in most scenarios. By default, Visual Studio tries to embed the manifest when it builds a project from source files; see Manifest Generation in Visual Studio for more information. However if an application is built by using nmake, some changes to the existing makefile are necessary. This section demonstrates how to change existing makefiles to automatically embed the manifest inside the final binary.

Two approaches

There are two ways to embed the manifest inside an application or library.

  • If you are not doing an incremental build you can directly embed the manifest using a command line similar to the following as a post-build step:

    mt.exe –manifest MyApp.exe.manifest -outputresource:MyApp.exe;1

    or

    mt.exe –manifest MyLibrary.dll.manifest -outputresource:MyLibrary.dll;2

    (1 for an EXE, 2 for a DLL.)

  • If you are doing an incremental build, directly editing the resource as shown here will disable incremental building and cause a full rebuild; therefore a different approach should be taken:

    • Link the binary to generate the MyApp.exe.manifest file.

    • Convert the manifest to a resource file.

    • Re-link (incrementally) to embed the manifest resource into the binary.

The following examples show how to change makefiles to incorporate both techniques.

Makefiles (Before)

Consider the nmake script for MyApp.exe, a simple application built from one file:

# build MyApp.exe
!if "$(DEBUG)" == "1"
CPPFLAGS=$(CPPFLAGS) /MDd
LFLAGS=$(LFLAGS) /INCREMENTAL
!else
CPPFLAGS=$(CPPFLAGS) /MD
!endif

MyApp.exe : MyApp.obj
    link $** /out:$@ $(LFLAGS)

MyApp.obj : MyApp.cpp

clean : 
    del MyApp.obj MyApp.exe

If this script is run unchanged with Visual C++, it successfully creates MyApp.exe. It also creates the external manifest file MyApp.exe.manifest, for use by the operating system to load dependent assemblies at runtime.

The nmake script for MyLibrary.dll looks very similar:

# build MyLibrary.dll
!if "$(DEBUG)" == "1"
CPPFLAGS=$(CPPFLAGS) /MDd
LFLAGS=$(LFLAGS) /DLL /INCREMENTAL

!else
CPPFLAGS=$(CPPFLAGS) /MD
LFLAGS=$(LFLAGS) /DLL

!endif

MyLibrary.dll : MyLibrary.obj
    link $** /out:$@ $(LFLAGS)

MyLibrary.obj : MyLibrary.cpp

clean : 
    del MyLibrary.obj MyLibrary.dll

Makefiles (After)

To build with embedded manifests you have to make four small changes to the original makefiles. For the MyApp.exe makefile:

# build MyApp.exe
!include makefile.inc
#^^^^^^^^^^^^^^^^^^^^ Change #1. (Add full path if necessary.)

!if "$(DEBUG)" == "1"
CPPFLAGS=$(CPPFLAGS) /MDd
LFLAGS=$(LFLAGS) /INCREMENTAL
!else
CPPFLAGS=$(CPPFLAGS) /MD
!endif

MyApp.exe : MyApp.obj
    link $** /out:$@ $(LFLAGS)
    $(_VC_MANIFEST_EMBED_EXE)
#^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Change #2

MyApp.obj : MyApp.cpp

clean : 
    del MyApp.obj MyApp.exe
    $(_VC_MANIFEST_CLEAN)
#^^^^^^^^^^^^^^^^^^^^^^^^ Change #3

!include makefile.targ.inc
#^^^^^^^^^^^^^^^^^^^^^^^^^ Change #4. (Add full path if necessary.)

For the MyLibrary.dll makefile:

# build MyLibrary.dll
!include makefile.inc
#^^^^^^^^^^^^^^^^^^^^ Change #1. (Add full path if necessary.)

!if "$(DEBUG)" == "1"
CPPFLAGS=$(CPPFLAGS) /MDd
LFLAGS=$(LFLAGS) /DLL /INCREMENTAL

!else
CPPFLAGS=$(CPPFLAGS) /MD
LFLAGS=$(LFLAGS) /DLL

!endif

MyLibrary.dll : MyLibrary.obj
    link $** /out:$@ $(LFLAGS)
    $(_VC_MANIFEST_EMBED_DLL)
#^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Change #2.

MyLibrary.obj : MyLibrary.cpp

clean : 
    del MyLibrary.obj MyLibrary.dll
    $(_VC_MANIFEST_CLEAN)
#^^^^^^^^^^^^^^^^^^^^^^^^ Change #3.

!include makefile.targ.inc
#^^^^^^^^^^^^^^^^^^^^^^^^^ Change #4. (Add full path if necessary.)

The makefiles now include two files that do the real work, makefile.inc and makefile.targ.inc.

Create makefile.inc and copy the following into it:

# makefile.inc -- Include this file into existing makefile at the very top.

# _VC_MANIFEST_INC specifies whether build is incremental (1 - incremental).
# _VC_MANIFEST_BASENAME specifies name of a temporary resource file.

!if "$(DEBUG)" == "1"
CPPFLAGS=$(CPPFLAGS) /MDd
LFLAGS=$(LFLAGS) /INCREMENTAL
_VC_MANIFEST_INC=1
_VC_MANIFEST_BASENAME=__VC90.Debug

!else
CPPFLAGS=$(CPPFLAGS) /MD
_VC_MANIFEST_INC=0
_VC_MANIFEST_BASENAME=__VC90

!endif

####################################################
# Specifying name of temporary resource file used only in incremental builds:

!if "$(_VC_MANIFEST_INC)" == "1"
_VC_MANIFEST_AUTO_RES=$(_VC_MANIFEST_BASENAME).auto.res
!else
_VC_MANIFEST_AUTO_RES=
!endif

####################################################
# _VC_MANIFEST_EMBED_EXE - command to embed manifest in EXE:

!if "$(_VC_MANIFEST_INC)" == "1"

#MT_SPECIAL_RETURN=1090650113
#MT_SPECIAL_SWITCH=-notify_resource_update
MT_SPECIAL_RETURN=0
MT_SPECIAL_SWITCH=
_VC_MANIFEST_EMBED_EXE= \
if exist $@.manifest mt.exe -manifest $@.manifest -out:$(_VC_MANIFEST_BASENAME).auto.manifest $(MT_SPECIAL_SWITCH) & \
if "%ERRORLEVEL%" == "$(MT_SPECIAL_RETURN)" \
rc /r $(_VC_MANIFEST_BASENAME).auto.rc & \
link $** /out:$@ $(LFLAGS)

!else

_VC_MANIFEST_EMBED_EXE= \
if exist $@.manifest mt.exe -manifest $@.manifest -outputresource:$@;1

!endif

####################################################
# _VC_MANIFEST_CLEAN - command to clean resources files generated temporarily:

!if "$(_VC_MANIFEST_INC)" == "1"

_VC_MANIFEST_CLEAN=-del $(_VC_MANIFEST_BASENAME).auto.res \
    $(_VC_MANIFEST_BASENAME).auto.rc \
    $(_VC_MANIFEST_BASENAME).auto.manifest

!else

_VC_MANIFEST_CLEAN=

!endif

# End of makefile.inc 
####################################################

Now create makefile.targ.inc and copy the following into it:

# makefile.targ.inc - include this at the very bottom of the existing makefile

####################################################
# Commands to generate initial empty manifest file and the RC file
# that references it, and for generating the .res file:

$(_VC_MANIFEST_BASENAME).auto.res : $(_VC_MANIFEST_BASENAME).auto.rc

$(_VC_MANIFEST_BASENAME).auto.rc : $(_VC_MANIFEST_BASENAME).auto.manifest
    type <<$@
#include <winuser.h>
1RT_MANIFEST"$(_VC_MANIFEST_BASENAME).auto.manifest"
<< KEEP

$(_VC_MANIFEST_BASENAME).auto.manifest :
    type <<$@
<?xml version='1.0' encoding='UTF-8' standalone='yes'?>
<assembly xmlns='urn:schemas-microsoft-com:asm.v1' manifestVersion='1.0'>
</assembly>
<< KEEP

# end of makefile.targ.inc

See Also

Concepts

Understanding Manifest Generation for C/C++ Programs